Could you correct it, thanks so much

My role model is my fifth sister. Her name is Mai, and she is a very beautiful and gentle person. She sacrificed everything for her siblings. When she was 12 years old, and my family was poor, there was a Cai luong show in my village. Many of her friends came to the theater. My sister didn't have any money, so she sold guava in order to earn money for a ticket. After school, she looked over our younger sisters and brothers, so she didn’t have any time to hang out with her friends. It was a hard time for my family. She was good student, but my father decided stop her education because it was difficult to pay for her school. She cried so much, and insisted on continuing schooling. Her teacher came to my house to convince him that my sister should return to school, but it didn’t happen. When she was 18 years old, she left house to do business in a far away place. She would always send money back to take care of our school expenses. Every year, at Tet's holiday, she always buys clothes and things for us. Fortunately, she was born in my family. I love her so much, and she always is the idol of my life.

Hello! I'm Mia. I'm not a grammarian but I write and edit English content for a living here in Manila. We're very tolerant in terms of writing style. We would like the piece to be distinct while maintaining its clarity. Everyone has a unique way of expressing themselves or ideas. Editor's often call this, "voice". 

In connection to what I've mentioned above, and without further delay, please find my corrections and comments in yellow below: 

Could You Correct It? Thanks So Much. <(Every word is capitalized like this because it's the title. We call it Title Case)

My role model is my sister Mai <(It's just clearer this way). She is a very beautiful and very <(Added this just for consistency) a gentle person. She sacrificed everything for us <(Did you want to communicate this by any chance?), her siblings.

(New paragraph, because you're slightly moving towards another topic.)>When she <(did you really mean your sister or you?) was 12 years old, our <(Because both you and your sister belong to the family) family was poor, there was a Cai Luong show in my village. Many of her friends went<(It took place in the past and this is a better way of saying it.) to the theater. My sister didn't have any money for the ticket, so she sold guava to earn money so she could buy the<(better) ticket.

(New paragraph, because you're slightly moving towards another topic.)>After school, she looks after our younger siblings<(better)>and she didn’t have anytime to hang out with her friends<(unless she only has one friend).

(New paragraph, because you're slightly moving towards another topic.)>It was a hard time for my family, so my father decided stop sending her to school even if she was a good student. She cried so much and insisted that my father send her back to school. Her teacher then came to our house to convince my father so my sister could continue studying, but it didn’t happen.

At 18 years old, she left home to work somewhere far<(better if you could say where. Was it in another city? Overseas? ). She would always send <(Google subject-verb agreement. You wrote "would" so your verb should be "send") money for our tuition fee. Every year, at Tet's holiday, she always remembers to buy clothes and things<(gifts? or necessities) for our family. We're lucky to have her in the family. I love her so much and she will always be my idol for life.

Could you correct it? Thank you so much (in advance).

My role model is my fifth sister, her name is Mai. She is very beautiful and a gentle person. She sacrifices everything for her family.

My family was poor, and this one time when Mai was 12 years old there was a Cai luong show in my village, and many of her friends went to the theater, but my sister didn't have any money for a ticket, so she went to sell guava in order to earn money for ticket.

After school she looked over our younger sisters and brothers, so she didn’t have anytime to hang out with her friend(friends). It was a hard time for my family.

(You could have wrote "It was a hard time for my family, as my family was/is poor.")

She was good student, but my father decided stop her studies because it was too difficult to pay for the schools expenses. She cried so much and insisted that father (he) let her continue going to school. Her teacher came to my house to convince him for my sister to return to school, but it never happened.

When she was 18 years old, she left the house for business very far away. She would always send money back to take care of our school expenses.

Every year at Tet's holiday, she will never forget to buy clothing, and things for us.

Fortunately (or you can say "I'm lucky or I'm glad"), she was born in my family. I love her so much and she'll always be the idol of my life.